LONGEVITY OF FISHES IN CAPTIVITY, 



WITH SPECIAL REFERENCE TO THOSE 



KEPT IN THE NEW YORK AQUARIUM 



Ross F. NiGRELLI 

 New York Aquarium 



The New York Aquarium, at one time or another during its 

 history, has exhibited for varying periods of time fishes 

 representing 33 of the 57 known orders. This figure is more 

 spectacular when it is reaUzed that 10 of the 57 orders contain 

 species restricted to fife in the benthic areas of the seas, which 

 have never been brought to the surface ahve long enough to 

 exhibit. The orders, as listed by Berg (1947), contain 425 

 families, at least 50 of them deep-sea forms. The New York 

 Aquarium has exhibited species representative of 152 families. 

 Other aquaria have probably kept fishes of another five or six 

 orders, involving an additional 25 families. Therefore, it is 

 apparently possible to maintain in captivity fishes represent- 

 ing 38 of the 57 orders and from 175-250 of the 425 families. 

 However, only relatively few of the estimated 25,000 species 

 have ever been captured and kept alive in aquaria; the exact 

 number has never been determined. Jordan, Evermann and 

 Clark (1930) list 4,137 species in the North and Middle Ameri- 

 can waters, and probably only a little more than one-fourth 

 of these have ever been exhibited. Breder (19366) summarizes 

 some of the environmental and physiological barriers that 

 may be limiting factors for the successful maintenance of 

 many species. He concedes, however, that these barriers 

 may be overcome and that some day it may be possible to 

 exhibit species not heretofore shown, including the exotic life 

 in the great depths of the oceans. 



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